This invention relates to adjustable tilt chairs and, more particularly, to an improved construction of chair with pneumatically controlled back and seat angle adjustment. A large number of adjustable chairs have been designed in the past which are intended for use in the seats of motor vehicles, aircraft, railway cars and buses, exemplified in U.S. Pat. No. 2,132,363 (Thomas et al.) and U.S. Pat. No. 3,810,674 (Svensson). Electrically or hydraulically controlled chairs having occupant assisting features whereby the back and seat members tilt as required to help the user in moving between seated and standing positions (e.g. orthopaedic chairs) are also exemplified in a number of prior patents, e.g. U.S. Pat. No. 4,632,455 (Schiller et al.) and U.S. Pat. No. 5,383,709 (Chaney et al.).
None of the existing designs are entirely satisfactory as chairs for use at meetings and lectures. Many known adjustable chairs have large and unwieldy bases which can lead to repetitive contact with and scuffing of the shoes of a user seated in a long and taxing meeting. Many known chairs have a good range of adjustability, but an adjustment mechanism whose use is overly obtrusive and insufficiently silent to lend itself to chairs around a boardroom table, for example.
It is an object of the present invention to provide a readily moveable adjustable chair with a pneumatic action having a simple lift lever manual control.
It is a further object of the invention to provide an improved chair as aforesaid which will permit continuous adjustment over a range of comfortable positions from a forward tilt (for poring over documents) to substantial recline for freeform conversation or solitary contemplation.
With a view to overcoming the disadvantages of the prior art and achieving the aforementioned objects, according to the invention there is provided a chair with adjustable seating angle which comprises a pair of vertical side walls, having contoured upper edge surface which serve as comfortable arm rests. These sides/arm rests of the chair are supported in spaced parallel relationship by an elongate cross-member extending between the walls below seat level. An integral chair back and seat assembly which is positioned between the side walls and pivotally mounted at the front of the seat portion thereof to the side walls for angular tilting under the action of pneumatic cylinder means connected between the centre of the cross-member and the underside of the seat portion. The tilting of the back/seat assembly is effected by manual actuating or deactuating of the pneumatic cylinder by a conveniently positioned control rod at the front of and just under the seat.
These and other objects and advantages of the present invention will be apparent from the detailed description which follows, when considered in conjunction with the accompanying drawings.